Current Conditions
Thornhill, Ontario
Wind
NW 3 mph4 km/h
Humidity
65%
Cloud Cover
42%
As of Monday, September 7, 2026 at 9:48 AM EDT
Today's Outlook
Day
Mostly cloudy and warm, with a high of 74°F24°C and morning low of 59°F15°C. Light wind from the WNW around 3 mph5 km/h.
Night
Partly cloudy, with a low around 63°F17°C. Light wind from the W around 3 mph5 km/h.
7-Day Forecast
| Day | Condition | High (°F) | Low (°F) | Precip (mm) | Cloud Cover (%) | Wind (mph) | |
|---|---|---|---|---|---|---|---|
| Partly Cloudy | High 74°F24°C | Low 59°F15°C | Precip 0 in0 mm— | Cloud 54% | Wind WNW 3 mph5 km/h | Monday: Mostly cloudy and warm, with a high of 74°F24°C and morning low of 59°F15°C. Light wind from the WNW around 3 mph5 km/h. Monday Night: Partly cloudy, with a low around 63°F17°C. Light wind from the W around 3 mph5 km/h. | |
| Cloudy | High 74°F23°C | Low 59°F15°C | Precip 0 in0 mm— | Cloud 92% | Wind ESE 5 mph7 km/h | Tuesday: Overcast and warm, with a high of 74°F23°C and morning low of 60°F16°C. Breezy from the SE at 4 to 7 mph7 to 11 km/h. Tuesday Night: Overcast, with a low around 59°F15°C. Light wind from the E around 5 mph8 km/h. | |
| Light Rain | High 75°F24°C | Low 65°F19°C | Precip 0.32 in8.1 mm79% | Cloud 92% | Wind SW 9 mph15 km/h | Wednesday: Overcast and warm, with a high of 75°F24°C and morning low of 68°F20°C. Breezy from the SW at 10 to 13 mph17 to 21 km/h. 79% chance of light rain throughout the day. Humid. Wednesday Night: Overcast, with a low around 65°F19°C. Breezy from the SW at 8 to 12 mph13 to 19 km/h. 57% chance of light rain throughout the night. | |
| Partly Cloudy | High 73°F23°C | Low 59°F15°C | Precip 0.01 in0.2 mm7% | Cloud 56% | Wind WNW 10 mph15 km/h | Thursday: Mostly cloudy and warm, with a high of 73°F23°C and morning low of 64°F18°C. Breezy from the WNW at 11 to 12 mph17 to 20 km/h. Thursday Night: Partly cloudy, with a low around 59°F15°C. Breezy from the WNW at 8 to 10 mph14 to 16 km/h. | |
| Clear | High 72°F22°C | Low 53°F12°C | Precip 0 in0 mm— | Cloud 14% | Wind WSW 6 mph9 km/h | Friday: Mostly clear and warm, with a high of 72°F22°C and morning low of 54°F12°C. Light wind from the W around 5 mph8 km/h. Friday Night: Mostly clear, with a low around 53°F12°C. Breezy from the SW at 7 mph11 km/h. | |
| Drizzle | High 76°F25°C | Low 57°F14°C | Precip 0.03 in0.7 mm19% | Cloud 47% | Wind SSW 8 mph13 km/h | Saturday: Mostly cloudy and warm, with a high of 76°F25°C and morning low of 60°F15°C. Breezy from the S at 9 to 11 mph15 to 18 km/h. Saturday Night: Partly cloudy, with a low around 57°F14°C. Breezy from the SSW at 7 to 9 mph12 to 14 km/h. 19% chance of drizzle in the evening. | |
| Drizzle | High 73°F23°C | Low 60°F16°C | Precip 0.1 in2.6 mm22% | Cloud 55% | Wind WNW 8 mph13 km/h | Sunday: Mostly cloudy and warm, with a high of 73°F23°C and morning low of 63°F17°C. Breezy from the W at 8 to 10 mph13 to 16 km/h. 19% chance of drizzle throughout the day. Sunday Night: Mostly cloudy, with a low around 60°F16°C. Breezy from the WNW at 8 to 9 mph13 to 14 km/h. 22% chance of drizzle throughout the night. |
15-Day Forecast
| Day | High | Low | Precip | Cloud Cover | Condition | Wind | |
|---|---|---|---|---|---|---|---|
| MondaySep 7 | 74°F24°C | 59°F15°C | 0 in0 mm· — | 54% | Partly Cloudy | WNW 3 mph5 km/h | |
DayMostly cloudy and warm, with a high of 74°F24°C and morning low of 59°F15°C. Light wind from the WNW around 3 mph5 km/h. NightPartly cloudy, with a low around 63°F17°C. Light wind from the W around 3 mph5 km/h. | |||||||
| TuesdaySep 8 | 74°F23°C | 59°F15°C | 0 in0 mm· — | 92% | Cloudy | ESE 5 mph7 km/h | |
DayOvercast and warm, with a high of 74°F23°C and morning low of 60°F16°C. Breezy from the SE at 4 to 7 mph7 to 11 km/h. NightOvercast, with a low around 59°F15°C. Light wind from the E around 5 mph8 km/h. | |||||||
| WednesdaySep 9 | 75°F24°C | 65°F19°C | 0.32 in8.1 mm· 79% | 92% | Light Rain | SW 9 mph15 km/h | |
DayOvercast and warm, with a high of 75°F24°C and morning low of 68°F20°C. Breezy from the SW at 10 to 13 mph17 to 21 km/h. 79% chance of light rain throughout the day. Humid. NightOvercast, with a low around 65°F19°C. Breezy from the SW at 8 to 12 mph13 to 19 km/h. 57% chance of light rain throughout the night. | |||||||
| ThursdaySep 10 | 73°F23°C | 59°F15°C | 0.01 in0.2 mm· 7% | 56% | Partly Cloudy | WNW 10 mph15 km/h | |
DayMostly cloudy and warm, with a high of 73°F23°C and morning low of 64°F18°C. Breezy from the WNW at 11 to 12 mph17 to 20 km/h. NightPartly cloudy, with a low around 59°F15°C. Breezy from the WNW at 8 to 10 mph14 to 16 km/h. | |||||||
| FridaySep 11 | 72°F22°C | 53°F12°C | 0 in0 mm· — | 14% | Clear | WSW 6 mph9 km/h | |
DayMostly clear and warm, with a high of 72°F22°C and morning low of 54°F12°C. Light wind from the W around 5 mph8 km/h. NightMostly clear, with a low around 53°F12°C. Breezy from the SW at 7 mph11 km/h. | |||||||
| SaturdaySep 12 | 76°F25°C | 57°F14°C | 0.03 in0.7 mm· 19% | 47% | Drizzle | SSW 8 mph13 km/h | |
DayMostly cloudy and warm, with a high of 76°F25°C and morning low of 60°F15°C. Breezy from the S at 9 to 11 mph15 to 18 km/h. NightPartly cloudy, with a low around 57°F14°C. Breezy from the SSW at 7 to 9 mph12 to 14 km/h. 19% chance of drizzle in the evening. | |||||||
| SundaySep 13 | 73°F23°C | 60°F16°C | 0.1 in2.6 mm· 22% | 55% | Drizzle | WNW 8 mph13 km/h | |
DayMostly cloudy and warm, with a high of 73°F23°C and morning low of 63°F17°C. Breezy from the W at 8 to 10 mph13 to 16 km/h. 19% chance of drizzle throughout the day. NightMostly cloudy, with a low around 60°F16°C. Breezy from the WNW at 8 to 9 mph13 to 14 km/h. 22% chance of drizzle throughout the night. | |||||||
| MondaySep 14 | 67°F20°C | 56°F14°C | 0.09 in2.4 mm· 16% | 55% | Drizzle | NNW 8 mph13 km/h | |
DayMostly cloudy and mild, with a high of 67°F20°C and morning low of 57°F14°C. Breezy from the NNW at 8 to 9 mph14 to 14 km/h. 16% chance of drizzle throughout the day. NightPartly cloudy, with a low around 56°F14°C. Breezy from the NNW at 8 mph13 km/h. 15% chance of drizzle throughout the night. | |||||||
| TuesdaySep 15 | 69°F21°C | 56°F13°C | 0.18 in4.5 mm· 21% | 63% | Showers | S 9 mph14 km/h | |
DayMostly cloudy and warm, with a high of 69°F21°C and morning low of 57°F14°C. Breezy from the S at 9 to 10 mph15 to 15 km/h. 20% chance of showers throughout the day. NightMostly cloudy, with a low around 56°F13°C. Breezy from the SSE at 8 to 9 mph13 to 14 km/h. 21% chance of showers throughout the night. | |||||||
| WednesdaySep 16 | 70°F21°C | 59°F15°C | 0.11 in2.7 mm· 21% | 63% | Showers | SSW 8 mph13 km/h | |
DayMostly cloudy and warm, with a high of 70°F21°C and morning low of 59°F15°C. Breezy from the SSW at 8 to 9 mph13 to 14 km/h. 15% chance of drizzle throughout the day. NightMostly cloudy, with a low around 59°F15°C. Breezy from the SSW at 8 to 9 mph13 to 14 km/h. 21% chance of showers throughout the night. | |||||||
| ThursdaySep 17 | 69°F21°C | 59°F15°C | 0.11 in2.9 mm· 22% | 64% | Drizzle | W 8 mph13 km/h | |
DayMostly cloudy and warm, with a high of 69°F21°C and morning low of 60°F15°C. Breezy from the WSW at 8 to 9 mph13 to 14 km/h. 22% chance of drizzle throughout the day. NightMostly cloudy, with a low around 59°F15°C. Breezy from the WNW at 7 to 8 mph12 to 12 km/h. 17% chance of drizzle throughout the night. | |||||||
| FridaySep 18 | 67°F20°C | 57°F14°C | 0.13 in3.4 mm· 22% | 57% | Showers | NW 8 mph13 km/h | |
DayMostly cloudy and mild, with a high of 67°F20°C and morning low of 57°F14°C. Breezy from the WNW at 9 mph14 km/h. 22% chance of drizzle throughout the day. NightMostly cloudy, with a low around 57°F14°C. Breezy from the NW at 8 mph13 km/h. 21% chance of showers throughout the night. | |||||||
| SaturdaySep 19 | 66°F19°C | 54°F12°C | 0.09 in2.2 mm· 19% | 56% | Drizzle | WNW 8 mph13 km/h | |
DayMostly cloudy and mild, with a high of 66°F19°C and morning low of 55°F13°C. Breezy from the W at 8 to 9 mph14 to 15 km/h. 19% chance of drizzle throughout the day. NightMostly cloudy, with a low around 54°F12°C. Breezy from the WNW at 8 mph12 km/h. 15% chance of drizzle throughout the night. | |||||||
| SundaySep 20 | 65°F19°C | 54°F12°C | 0.09 in2.3 mm· 16% | 56% | Drizzle | WNW 8 mph13 km/h | |
DayMostly cloudy and mild, with a high of 65°F19°C and morning low of 54°F12°C. Breezy from the W at 9 mph14 km/h. 16% chance of drizzle throughout the day. NightMostly cloudy, with a low around 54°F12°C. Breezy from the WNW at 8 mph13 km/h. 14% chance of drizzle throughout the night. | |||||||
| MondaySep 21 | 63°F17°C | 52°F11°C | 0.11 in2.9 mm· 16% | 59% | Drizzle | NNW 8 mph13 km/h | |
DayMostly cloudy and mild, with a high of 63°F17°C and morning low of 52°F11°C. Breezy from the N at 9 mph14 km/h. 16% chance of drizzle throughout the day. Dry air. NightMostly cloudy, with a low around 52°F11°C. Breezy from the NNW at 8 mph13 km/h. 16% chance of drizzle throughout the night. | |||||||
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Coordinates: 43.8150°N, 79.4242°W·Elevation: 175m·Timezone: America/Toronto·Population: 115,292